mapbox-gl/src/ui/map.js

A WebGL interactive maps library

// @flow

import { extend, bindAll, warnOnce, uniqueId } from '../util/util';
import browser from '../util/browser';
import window from '../util/window';
const { HTMLImageElement, HTMLElement } = window;
import DOM from '../util/dom';
import { getImage, getJSON, ResourceType } from '../util/ajax';
import { RequestManager } from '../util/mapbox';
import Style from '../style/style';
import EvaluationParameters from '../style/evaluation_parameters';
import Painter from '../render/painter';
import Transform from '../geo/transform';
import Hash from './hash';
import bindHandlers from './bind_handlers';
import Camera from './camera';
import LngLat from '../geo/lng_lat';
import LngLatBounds from '../geo/lng_lat_bounds';
import Point from '@mapbox/point-geometry';
import AttributionControl from './control/attribution_control';
import LogoControl from './control/logo_control';
import isSupported from '@mapbox/mapbox-gl-supported';
import { RGBAImage } from '../util/image';
import { Event, ErrorEvent } from '../util/evented';
import { MapMouseEvent } from './events';
import TaskQueue from '../util/task_queue';
import webpSupported from '../util/webp_supported';
import { setCacheLimits } from '../util/tile_request_cache';

import type {PointLike} from '@mapbox/point-geometry';
import type { RequestTransformFunction } from '../util/mapbox';
import type {LngLatLike} from '../geo/lng_lat';
import type {LngLatBoundsLike} from '../geo/lng_lat_bounds';
import type {StyleOptions, StyleSetterOptions} from '../style/style';
import type {MapEvent, MapDataEvent} from './events';
import type {CustomLayerInterface} from '../style/style_layer/custom_style_layer';
import type {StyleImageInterface} from '../style/style_image';

import type ScrollZoomHandler from './handler/scroll_zoom';
import type BoxZoomHandler from './handler/box_zoom';
import type DragRotateHandler from './handler/drag_rotate';
import type DragPanHandler from './handler/drag_pan';
import type KeyboardHandler from './handler/keyboard';
import type DoubleClickZoomHandler from './handler/dblclick_zoom';
import type TouchZoomRotateHandler from './handler/touch_zoom_rotate';
import type {TaskID} from '../util/task_queue';
import type {Cancelable} from '../types/cancelable';
import type {
    LayerSpecification,
    FilterSpecification,
    StyleSpecification,
    LightSpecification,
    SourceSpecification
} from '../style-spec/types';

type ControlPosition = 'top-left' | 'top-right' | 'bottom-left' | 'bottom-right';
/* eslint-disable no-use-before-define */
type IControl = {
    onAdd(map: Map): HTMLElement;
    onRemove(map: Map): void;

    +getDefaultPosition?: () => ControlPosition;
}
/* eslint-enable no-use-before-define */

type MapOptions = {
    hash?: boolean,
    interactive?: boolean,
    container: HTMLElement | string,
    bearingSnap?: number,
    attributionControl?: boolean,
    customAttribution?: string | Array<string>,
    logoPosition?: ControlPosition,
    failIfMajorPerformanceCaveat?: boolean,
    preserveDrawingBuffer?: boolean,
    antialias?: boolean,
    refreshExpiredTiles?: boolean,
    maxBounds?: LngLatBoundsLike,
    scrollZoom?: boolean,
    minZoom?: ?number,
    maxZoom?: ?number,
    boxZoom?: boolean,
    dragRotate?: boolean,
    dragPan?: boolean,
    keyboard?: boolean,
    doubleClickZoom?: boolean,
    touchZoomRotate?: boolean,
    trackResize?: boolean,
    center?: LngLatLike,
    zoom?: number,
    bearing?: number,
    pitch?: number,
    renderWorldCopies?: boolean,
    maxTileCacheSize?: number,
    transformRequest?: RequestTransformFunction,
    accessToken: string
};

const defaultMinZoom = 0;
const defaultMaxZoom = 22;
const defaultOptions = {
    center: [0, 0],
    zoom: 0,
    bearing: 0,
    pitch: 0,

    minZoom: defaultMinZoom,
    maxZoom: defaultMaxZoom,

    interactive: true,
    scrollZoom: true,
    boxZoom: true,
    dragRotate: true,
    dragPan: true,
    keyboard: true,
    doubleClickZoom: true,
    touchZoomRotate: true,

    bearingSnap: 7,
    clickTolerance: 3,

    hash: false,
    attributionControl: true,

    failIfMajorPerformanceCaveat: false,
    preserveDrawingBuffer: false,
    trackResize: true,
    renderWorldCopies: true,
    refreshExpiredTiles: true,
    maxTileCacheSize: null,
    localIdeographFontFamily: 'sans-serif',
    transformRequest: null,
    accessToken: null,
    fadeDuration: 300,
    crossSourceCollisions: true
};

/**
 * The `Map` object represents the map on your page. It exposes methods
 * and properties that enable you to programmatically change the map,
 * and fires events as users interact with it.
 *
 * You create a `Map` by specifying a `container` and other options.
 * Then Mapbox GL JS initializes the map on the page and returns your `Map`
 * object.
 *
 * @extends Evented
 * @param {Object} options
 * @param {HTMLElement|string} options.container The HTML element in which Mapbox GL JS will render the map, or the element's string `id`. The specified element must have no children.
 * @param {number} [options.minZoom=0] The minimum zoom level of the map (0-24).
 * @param {number} [options.maxZoom=22] The maximum zoom level of the map (0-24).
 * @param {Object|string} [options.style] The map's Mapbox style. This must be an a JSON object conforming to
 * the schema described in the [Mapbox Style Specification](https://mapbox.com/mapbox-gl-style-spec/), or a URL to
 * such JSON.
 *
 * To load a style from the Mapbox API, you can use a URL of the form `mapbox://styles/:owner/:style`,
 * where `:owner` is your Mapbox account name and `:style` is the style ID. Or you can use one of the following
 * [the predefined Mapbox styles](https://www.mapbox.com/maps/):
 *
 *  * `mapbox://styles/mapbox/streets-v10`
 *  * `mapbox://styles/mapbox/outdoors-v10`
 *  * `mapbox://styles/mapbox/light-v9`
 *  * `mapbox://styles/mapbox/dark-v9`
 *  * `mapbox://styles/mapbox/satellite-v9`
 *  * `mapbox://styles/mapbox/satellite-streets-v10`
 *  * `mapbox://styles/mapbox/navigation-preview-day-v2`
 *  * `mapbox://styles/mapbox/navigation-preview-night-v2`
 *  * `mapbox://styles/mapbox/navigation-guidance-day-v2`
 *  * `mapbox://styles/mapbox/navigation-guidance-night-v2`
 *
 * Tilesets hosted with Mapbox can be style-optimized if you append `?optimize=true` to the end of your style URL, like `mapbox://styles/mapbox/streets-v9?optimize=true`.
 * Learn more about style-optimized vector tiles in our [API documentation](https://www.mapbox.com/api-documentation/maps/#retrieve-tiles).
 *
 * @param {boolean} [options.hash=false] If `true`, the map's position (zoom, center latitude, center longitude, bearing, and pitch) will be synced with the hash fragment of the page's URL.
 *   For example, `http://path/to/my/page.html#2.59/39.26/53.07/-24.1/60`.
 * @param {boolean} [options.interactive=true] If `false`, no mouse, touch, or keyboard listeners will be attached to the map, so it will not respond to interaction.
 * @param {number} [options.bearingSnap=7] The threshold, measured in degrees, that determines when the map's
 *   bearing will snap to north. For example, with a `bearingSnap` of 7, if the user rotates
 *   the map within 7 degrees of north, the map will automatically snap to exact north.
 * @param {boolean} [options.pitchWithRotate=true] If `false`, the map's pitch (tilt) control with "drag to rotate" interaction will be disabled.
 * @param {number} [options.clickTolerance=3] The max number of pixels a user can shift the mouse pointer during a click for it to be considered a valid click (as opposed to a mouse drag).
 * @param {boolean} [options.attributionControl=true] If `true`, an {@link AttributionControl} will be added to the map.
 * @param {string | Array<string>} [options.customAttribution] String or strings to show in an {@link AttributionControl}. Only applicable if `options.attributionControl` is `true`.
 * @param {string} [options.logoPosition='bottom-left'] A string representing the position of the Mapbox wordmark on the map. Valid options are `top-left`,`top-right`, `bottom-left`, `bottom-right`.
 * @param {boolean} [options.failIfMajorPerformanceCaveat=false] If `true`, map creation will fail if the performance of Mapbox
 *   GL JS would be dramatically worse than expected (i.e. a software renderer would be used).
 * @param {boolean} [options.preserveDrawingBuffer=false] If `true`, the map's canvas can be exported to a PNG using `map.getCanvas().toDataURL()`. This is `false` by default as a performance optimization.
 * @param {boolean} [options.antialias] If `true`, the gl context will be created with MSAA antialiasing, which can be useful for antialiasing custom layers. this is `false` by default as a performance optimization.
 * @param {boolean} [options.refreshExpiredTiles=true] If `false`, the map won't attempt to re-request tiles once they expire per their HTTP `cacheControl`/`expires` headers.
 * @param {LngLatBoundsLike} [options.maxBounds] If set, the map will be constrained to the given bounds.
 * @param {boolean|Object} [options.scrollZoom=true] If `true`, the "scroll to zoom" interaction is enabled. An `Object` value is passed as options to {@link ScrollZoomHandler#enable}.
 * @param {boolean} [options.boxZoom=true] If `true`, the "box zoom" interaction is enabled (see {@link BoxZoomHandler}).
 * @param {boolean} [options.dragRotate=true] If `true`, the "drag to rotate" interaction is enabled (see {@link DragRotateHandler}).
 * @param {boolean} [options.dragPan=true] If `true`, the "drag to pan" interaction is enabled (see {@link DragPanHandler}).
 * @param {boolean} [options.keyboard=true] If `true`, keyboard shortcuts are enabled (see {@link KeyboardHandler}).
 * @param {boolean} [options.doubleClickZoom=true] If `true`, the "double click to zoom" interaction is enabled (see {@link DoubleClickZoomHandler}).
 * @param {boolean|Object} [options.touchZoomRotate=true] If `true`, the "pinch to rotate and zoom" interaction is enabled. An `Object` value is passed as options to {@link TouchZoomRotateHandler#enable}.
 * @param {boolean} [options.trackResize=true]  If `true`, the map will automatically resize when the browser window resizes.
 * @param {LngLatLike} [options.center=[0, 0]] The inital geographical centerpoint of the map. If `center` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `[0, 0]` Note: Mapbox GL uses longitude, latitude coordinate order (as opposed to latitude, longitude) to match GeoJSON.
 * @param {number} [options.zoom=0] The initial zoom level of the map. If `zoom` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `0`.
 * @param {number} [options.bearing=0] The initial bearing (rotation) of the map, measured in degrees counter-clockwise from north. If `bearing` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `0`.
 * @param {number} [options.pitch=0] The initial pitch (tilt) of the map, measured in degrees away from the plane of the screen (0-60). If `pitch` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `0`.
 * @param {LngLatBoundsLike} [options.bounds] The initial bounds of the map. If `bounds` is specified, it overrides `center` and `zoom` constructor options.
 * @param {Object} [options.fitBoundsOptions] A [`fitBounds`](#map#fitbounds) options object to use _only_ when fitting the initial `bounds` provided above.
 * @param {boolean} [options.renderWorldCopies=true]  If `true`, multiple copies of the world will be rendered, when zoomed out.
 * @param {number} [options.maxTileCacheSize=null]  The maximum number of tiles stored in the tile cache for a given source. If omitted, the cache will be dynamically sized based on the current viewport.
 * @param {string} [options.localIdeographFontFamily='sans-serif'] Defines a CSS
 *   font-family for locally overriding generation of glyphs in the 'CJK Unified Ideographs', 'Hiragana', 'Katakana' and 'Hangul Syllables' ranges.
 *   In these ranges, font settings from the map's style will be ignored, except for font-weight keywords (light/regular/medium/bold).
 *   Set to `false`, to enable font settings from the map's style for these glyph ranges.
 *   The purpose of this option is to avoid bandwidth-intensive glyph server requests. (see [Use locally generated ideographs](https://www.mapbox.com/mapbox-gl-js/example/local-ideographs))
 * @param {RequestTransformFunction} [options.transformRequest=null] A callback run before the Map makes a request for an external URL. The callback can be used to modify the url, set headers, or set the credentials property for cross-origin requests.
 *   Expected to return an object with a `url` property and optionally `headers` and `credentials` properties.
 * @param {boolean} [options.collectResourceTiming=false] If `true`, Resource Timing API information will be collected for requests made by GeoJSON and Vector Tile web workers (this information is normally inaccessible from the main Javascript thread). Information will be returned in a `resourceTiming` property of relevant `data` events.
 * @param {number} [options.fadeDuration=300] Controls the duration of the fade-in/fade-out animation for label collisions, in milliseconds. This setting affects all symbol layers. This setting does not affect the duration of runtime styling transitions or raster tile cross-fading.
 * @param {boolean} [options.crossSourceCollisions=true] If `true`, symbols from multiple sources can collide with each other during collision detection. If `false`, collision detection is run separately for the symbols in each source.
 * @param {string} [options.accessToken=null] If specified, map will use this token instead of the one defined in mapboxgl.accessToken.

 * @example
 * var map = new mapboxgl.Map({
 *   container: 'map',
 *   center: [-122.420679, 37.772537],
 *   zoom: 13,
 *   style: style_object,
 *   hash: true,
 *   transformRequest: (url, resourceType)=> {
 *     if(resourceType === 'Source' && url.startsWith('http://myHost')) {
 *       return {
 *        url: url.replace('http', 'https'),
 *        headers: { 'my-custom-header': true},
 *        credentials: 'include'  // Include cookies for cross-origin requests
 *      }
 *     }
 *   }
 * });
 * @see [Display a map](https://www.mapbox.com/mapbox-gl-js/examples/)
 */
class Map extends Camera {
    style: Style;
    painter: Painter;

    _container: HTMLElement;
    _missingCSSCanary: HTMLElement;
    _canvasContainer: HTMLElement;
    _controlContainer: HTMLElement;
    _controlPositions: {[string]: HTMLElement};
    _interactive: ?boolean;
    _showTileBoundaries: ?boolean;
    _showCollisionBoxes: ?boolean;
    _showOverdrawInspector: boolean;
    _repaint: ?boolean;
    _vertices: ?boolean;
    _canvas: HTMLCanvasElement;
    _maxTileCacheSize: number;
    _frame: ?Cancelable;
    _styleDirty: ?boolean;
    _sourcesDirty: ?boolean;
    _placementDirty: ?boolean;
    _loaded: boolean;
    _trackResize: boolean;
    _preserveDrawingBuffer: boolean;
    _failIfMajorPerformanceCaveat: boolean;
    _antialias: boolean;
    _refreshExpiredTiles: boolean;
    _hash: Hash;
    _delegatedListeners: any;
    _fadeDuration: number;
    _crossSourceCollisions: boolean;
    _crossFadingFactor: number;
    _collectResourceTiming: boolean;
    _renderTaskQueue: TaskQueue;
    _controls: Array<IControl>;
    _mapId: number;
    _localIdeographFontFamily: string;
    _requestManager: RequestManager;

    /**
     * The map's {@link ScrollZoomHandler}, which implements zooming in and out with a scroll wheel or trackpad.
     */
    scrollZoom: ScrollZoomHandler;

    /**
     * The map's {@link BoxZoomHandler}, which implements zooming using a drag gesture with the Shift key pressed.
     */
    boxZoom: BoxZoomHandler;

    /**
     * The map's {@link DragRotateHandler}, which implements rotating the map while dragging with the right
     * mouse button or with the Control key pressed.
     */
    dragRotate: DragRotateHandler;

    /**
     * The map's {@link DragPanHandler}, which implements dragging the map with a mouse or touch gesture.
     */
    dragPan: DragPanHandler;

    /**
     * The map's {@link KeyboardHandler}, which allows the user to zoom, rotate, and pan the map using keyboard
     * shortcuts.
     */
    keyboard: KeyboardHandler;

    /**
     * The map's {@link DoubleClickZoomHandler}, which allows the user to zoom by double clicking.
     */
    doubleClickZoom: DoubleClickZoomHandler;

    /**
     * The map's {@link TouchZoomRotateHandler}, which allows the user to zoom or rotate the map with touch gestures.
     */
    touchZoomRotate: TouchZoomRotateHandler;

    constructor(options: MapOptions) {
        options = extend({}, defaultOptions, options);

        if (options.minZoom != null && options.maxZoom != null && options.minZoom > options.maxZoom) {
            throw new Error(`maxZoom must be greater than minZoom`);
        }

        const transform = new Transform(options.minZoom, options.maxZoom, options.renderWorldCopies);
        super(transform, options);

        this._interactive = options.interactive;
        this._maxTileCacheSize = options.maxTileCacheSize;
        this._failIfMajorPerformanceCaveat = options.failIfMajorPerformanceCaveat;
        this._preserveDrawingBuffer = options.preserveDrawingBuffer;
        this._antialias = options.antialias;
        this._trackResize = options.trackResize;
        this._bearingSnap = options.bearingSnap;
        this._refreshExpiredTiles = options.refreshExpiredTiles;
        this._fadeDuration = options.fadeDuration;
        this._crossSourceCollisions = options.crossSourceCollisions;
        this._crossFadingFactor = 1;
        this._collectResourceTiming = options.collectResourceTiming;
        this._renderTaskQueue = new TaskQueue();
        this._controls = [];
        this._mapId = uniqueId();

        this._requestManager = new RequestManager(options.transformRequest, options.accessToken);

        if (typeof options.container === 'string') {
            this._container = window.document.getElementById(options.container);
            if (!this._container) {
                throw new Error(`Container '${options.container}' not found.`);
            }
        } else if (options.container instanceof HTMLElement) {
            this._container = options.container;
        } else {
            throw new Error(`Invalid type: 'container' must be a String or HTMLElement.`);
        }

        if (options.maxBounds) {
            this.setMaxBounds(options.maxBounds);
        }

        bindAll([
            '_onWindowOnline',
            '_onWindowResize',
            '_contextLost',
            '_contextRestored'
        ], this);

        this._setupContainer();
        this._setupPainter();
        if (this.painter === undefined) {
            throw new Error(`Failed to initialize WebGL.`);
        }

        this.on('move', () => this._update(false));
        this.on('moveend', () => this._update(false));
        this.on('zoom', () => this._update(true));

        if (typeof window !== 'undefined') {
            window.addEventListener('online', this._onWindowOnline, false);
            window.addEventListener('resize', this._onWindowResize, false);
        }

        bindHandlers(this, options);

        this._hash = options.hash && (new Hash()).addTo(this);
        // don't set position from options if set through hash
        if (!this._hash || !this._hash._onHashChange()) {
            this.jumpTo({
                center: options.center,
                zoom: options.zoom,
                bearing: options.bearing,
                pitch: options.pitch
            });

            if (options.bounds) {
                this.resize();
                this.fitBounds(options.bounds, extend({}, options.fitBoundsOptions, { duration: 0 }));
            }
        }

        this.resize();

        this._localIdeographFontFamily = options.localIdeographFontFamily;
        if (options.style) this.setStyle(options.style, { localIdeographFontFamily: options.localIdeographFontFamily });

        if (options.attributionControl)
            this.addControl(new AttributionControl({ customAttribution: options.customAttribution }));

        this.addControl(new LogoControl(), options.logoPosition);

        this.on('style.load', () => {
            if (this.transform.unmodified) {
                this.jumpTo((this.style.stylesheet: any));
            }
        });
        this.on('data', (event: MapDataEvent) => {
            this._update(event.dataType === 'style');
            this.fire(new Event(`${event.dataType}data`, event));
        });
        this.on('dataloading', (event: MapDataEvent) => {
            this.fire(new Event(`${event.dataType}dataloading`, event));
        });
    }

    /*
    * Returns a unique number for this map instance which is used for the MapLoadEvent
    * to make sure we only fire one event per instantiated map object.
    * @private
    * @returns {number}
    */
    _getMapId() {
        return this._mapId;
    }

    /**
     * Adds a {@link IControl} to the map, calling `control.onAdd(this)`.
     *
     * @param {IControl} control The {@link IControl} to add.
     * @param {string} [position] position on the map to which the control will be added.
     * Valid values are `'top-left'`, `'top-right'`, `'bottom-left'`, and `'bottom-right'`. Defaults to `'top-right'`.
     * @returns {Map} `this`
     * @see [Display map navigation controls](https://www.mapbox.com/mapbox-gl-js/example/navigation/)
     */
    addControl(control: IControl, position?: ControlPosition) {
        if (position === undefined && control.getDefaultPosition) {
            position = control.getDefaultPosition();
        }
        if (position === undefined) {
            position = 'top-right';
        }
        if (!control || !control.onAdd) {
            return this.fire(new ErrorEvent(new Error(
                'Invalid argument to map.addControl(). Argument must be a control with onAdd and onRemove methods.')));
        }
        const controlElement = control.onAdd(this);
        this._controls.push(control);

        const positionContainer = this._controlPositions[position];
        if (position.indexOf('bottom') !== -1) {
            positionContainer.insertBefore(controlElement, positionContainer.firstChild);
        } else {
            positionContainer.appendChild(controlElement);
        }
        return this;
    }

    /**
     * Removes the control from the map.
     *
     * @param {IControl} control The {@link IControl} to remove.
     * @returns {Map} `this`
     */
    removeControl(control: IControl) {
        if (!control || !control.onRemove) {
            return this.fire(new ErrorEvent(new Error(
                'Invalid argument to map.removeControl(). Argument must be a control with onAdd and onRemove methods.')));
        }
        const ci = this._controls.indexOf(control);
        if (ci > -1) this._controls.splice(ci, 1);
        control.onRemove(this);
        return this;
    }

    /**
     * Resizes the map according to the dimensions of its
     * `container` element.
     *
     * This method must be called after the map's `container` is resized by another script,
     * or when the map is shown after being initially hidden with CSS.
     *
     * @param eventData Additional properties to be added to event objects of events triggered by this method.
     * @returns {Map} `this`
     */
    resize(eventData?: Object) {
        const dimensions = this._containerDimensions();
        const width = dimensions[0];
        const height = dimensions[1];

        this._resizeCanvas(width, height);
        this.transform.resize(width, height);
        this.painter.resize(width, height);

        this.fire(new Event('movestart', eventData))
            .fire(new Event('move', eventData))
            .fire(new Event('resize', eventData))
            .fire(new Event('moveend', eventData));
        return this;
    }

    /**
     * Returns the map's geographical bounds. When the bearing or pitch is non-zero, the visible region is not
     * an axis-aligned rectangle, and the result is the smallest bounds that encompasses the visible region.
     */
    getBounds(): LngLatBounds {
        return this.transform.getBounds();
    }

    /**
     * Returns the maximum geographical bounds the map is constrained to, or `null` if none set.
     */
    getMaxBounds(): LngLatBounds | null {
        return this.transform.getMaxBounds();
    }

    /**
     * Sets or clears the map's geographical bounds.
     *
     * Pan and zoom operations are constrained within these bounds.
     * If a pan or zoom is performed that would
     * display regions outside these bounds, the map will
     * instead display a position and zoom level
     * as close as possible to the operation's request while still
     * remaining within the bounds.
     *
     * @param {LngLatBoundsLike | null | undefined} bounds The maximum bounds to set. If `null` or `undefined` is provided, the function removes the map's maximum bounds.
     * @returns {Map} `this`
     */
    setMaxBounds(bounds: LngLatBoundsLike) {
        this.transform.setMaxBounds(LngLatBounds.convert(bounds));
        return this._update();
    }

    /**
     * Sets or clears the map's minimum zoom level.
     * If the map's current zoom level is lower than the new minimum,
     * the map will zoom to the new minimum.
     *
     * @param {number | null | undefined} minZoom The minimum zoom level to set (0-24).
     *   If `null` or `undefined` is provided, the function removes the current minimum zoom (i.e. sets it to 0).
     * @returns {Map} `this`
     */
    setMinZoom(minZoom?: ?number) {

        minZoom = minZoom === null || minZoom === undefined ? defaultMinZoom : minZoom;

        if (minZoom >= defaultMinZoom && minZoom <= this.transform.maxZoom) {
            this.transform.minZoom = minZoom;
            this._update();

            if (this.getZoom() < minZoom) this.setZoom(minZoom);

            return this;

        } else throw new Error(`minZoom must be between ${defaultMinZoom} and the current maxZoom, inclusive`);
    }

    /**
     * Returns the map's minimum allowable zoom level.
     *
     * @returns {number} minZoom
     */
    getMinZoom() { return this.transform.minZoom; }

    /**
     * Sets or clears the map's maximum zoom level.
     * If the map's current zoom level is higher than the new maximum,
     * the map will zoom to the new maximum.
     *
     * @param {number | null | undefined} maxZoom The maximum zoom level to set.
     *   If `null` or `undefined` is provided, the function removes the current maximum zoom (sets it to 22).
     * @returns {Map} `this`
     */
    setMaxZoom(maxZoom?: ?number) {

        maxZoom = maxZoom === null || maxZoom === undefined ? defaultMaxZoom : maxZoom;

        if (maxZoom >= this.transform.minZoom) {
            this.transform.maxZoom = maxZoom;
            this._update();

            if (this.getZoom() > maxZoom) this.setZoom(maxZoom);

            return this;

        } else throw new Error(`maxZoom must be greater than the current minZoom`);
    }

    /**
     * Returns the state of renderWorldCopies.
     *
     * @returns {boolean} renderWorldCopies
     */
    getRenderWorldCopies() { return this.transform.renderWorldCopies; }

    /**
     * Sets the state of renderWorldCopies.
     *
     * @param {boolean} renderWorldCopies If `true`, multiple copies of the world will be rendered, when zoomed out. `undefined` is treated as `true`, `null` is treated as `false`.
     * @returns {Map} `this`
     */
    setRenderWorldCopies(renderWorldCopies?: ?boolean) {
        this.transform.renderWorldCopies = renderWorldCopies;
        return this._update();
    }

    /**
     * Returns the map's maximum allowable zoom level.
     *
     * @returns {number} maxZoom
     */
    getMaxZoom() { return this.transform.maxZoom; }

    /**
     * Returns a {@link Point} representing pixel coordinates, relative to the map's `container`,
     * that correspond to the specified geographical location.
     *
     * @param {LngLatLike} lnglat The geographical location to project.
     * @returns {Point} The {@link Point} corresponding to `lnglat`, relative to the map's `container`.
     */
    project(lnglat: LngLatLike) {
        return this.transform.locationPoint(LngLat.convert(lnglat));
    }

    /**
     * Returns a {@link LngLat} representing geographical coordinates that correspond
     * to the specified pixel coordinates.
     *
     * @param {PointLike} point The pixel coordinates to unproject.
     * @returns {LngLat} The {@link LngLat} corresponding to `point`.
     * @see [Show polygon information on click](https://www.mapbox.com/mapbox-gl-js/example/polygon-popup-on-click/)
     */
    unproject(point: PointLike) {
        return this.transform.pointLocation(Point.convert(point));
    }

    /**
     * Returns true if the map is panning, zooming, rotating, or pitching due to a camera animation or user gesture.
     */
    isMoving(): boolean {
        return this._moving ||
            this.dragPan.isActive() ||
            this.dragRotate.isActive() ||
            this.scrollZoom.isActive();
    }

    /**
     * Returns true if the map is zooming due to a camera animation or user gesture.
     */
    isZooming(): boolean {
        return this._zooming ||
            this.scrollZoom.isZooming();
    }

    /**
     * Returns true if the map is rotating due to a camera animation or user gesture.
     */
    isRotating(): boolean {
        return this._rotating ||
            this.dragRotate.isActive();
    }

    /**
     * Adds a listener for events of a specified type.
     *
     * @method
     * @name on
     * @memberof Map
     * @instance
     * @param {string} type The event type to add a listen for.
     * @param {Function} listener The function to be called when the event is fired.
     *   The listener function is called with the data object passed to `fire`,
     *   extended with `target` and `type` properties.
     * @returns {Map} `this`
     */

    /**
     * Adds a listener for events of a specified type occurring on features in a specified style layer.
     *
     * @param {string} type The event type to listen for; one of `'mousedown'`, `'mouseup'`, `'click'`, `'dblclick'`,
     * `'mousemove'`, `'mouseenter'`, `'mouseleave'`, `'mouseover'`, `'mouseout'`, `'contextmenu'`, `'touchstart'`,
     * `'touchend'`, or `'touchcancel'`. `mouseenter` and `mouseover` events are triggered when the cursor enters
     * a visible portion of the specified layer from outside that layer or outside the map canvas. `mouseleave`
     * and `mouseout` events are triggered when the cursor leaves a visible portion of the specified layer, or leaves
     * the map canvas.
     * @param {string} layerId The ID of a style layer. Only events whose location is within a visible
     * feature in this layer will trigger the listener. The event will have a `features` property containing
     * an array of the matching features.
     * @param {Function} listener The function to be called when the event is fired.
     * @returns {Map} `this`
     */
    on(type: MapEvent, layerId: any, listener: any) {
        if (listener === undefined) {
            return super.on(type, layerId);
        }

        const delegatedListener = (() => {
            if (type === 'mouseenter' || type === 'mouseover') {
                let mousein = false;
                const mousemove = (e) => {
                    const features = this.getLayer(layerId) ? this.queryRenderedFeatures(e.point, {layers: [layerId]}) : [];
                    if (!features.length) {
                        mousein = false;
                    } else if (!mousein) {
                        mousein = true;
                        listener.call(this, new MapMouseEvent(type, this, e.originalEvent, {features}));
                    }
                };
                const mouseout = () => {
                    mousein = false;
                };
                return {layer: layerId, listener, delegates: {mousemove, mouseout}};
            } else if (type === 'mouseleave' || type === 'mouseout') {
                let mousein = false;
                const mousemove = (e) => {
                    const features = this.getLayer(layerId) ? this.queryRenderedFeatures(e.point, {layers: [layerId]}) : [];
                    if (features.length) {
                        mousein = true;
                    } else if (mousein) {
                        mousein = false;
                        listener.call(this, new MapMouseEvent(type, this, e.originalEvent));
                    }
                };
                const mouseout = (e) => {
                    if (mousein) {
                        mousein = false;
                        listener.call(this, new MapMouseEvent(type, this, e.originalEvent));
                    }
                };
                return {layer: layerId, listener, delegates: {mousemove, mouseout}};
            } else {
                const delegate = (e) => {
                    const features = this.getLayer(layerId) ? this.queryRenderedFeatures(e.point, {layers: [layerId]}) : [];
                    if (features.length) {
                        // Here we need to mutate the original event, so that preventDefault works as expected.
                        e.features = features;
                        listener.call(this, e);
                        delete e.features;
                    }
                };
                return {layer: layerId, listener, delegates: {[type]: delegate}};
            }
        })();

        this._delegatedListeners = this._delegatedListeners || {};
        this._delegatedListeners[type] = this._delegatedListeners[type] || [];
        this._delegatedListeners[type].push(delegatedListener);

        for (const event in delegatedListener.delegates) {
            this.on((event: any), delegatedListener.delegates[event]);
        }

        return this;
    }

    /**
     * Removes an event listener previously added with `Map#on`.
     *
     * @method
     * @name off
     * @memberof Map
     * @instance
     * @param {string} type The event type previously used to install the listener.
     * @param {Function} listener The function previously installed as a listener.
     * @returns {Map} `this`
     */

    /**
     * Removes an event listener for layer-specific events previously added with `Map#on`.
     *
     * @param {string} type The event type previously used to install the listener.
     * @param {string} layerId The layer ID previously used to install the listener.
     * @param {Function} listener The function previously installed as a listener.
     * @returns {Map} `this`
     */
    off(type: MapEvent, layerId: any, listener: any) {
        if (listener === undefined) {
            return super.off(type, layerId);
        }

        if (this._delegatedListeners && this._delegatedListeners[type]) {
            const listeners = this._delegatedListeners[type];
            for (let i = 0; i < listeners.length; i++) {
                const delegatedListener = listeners[i];
                if (delegatedListener.layer === layerId && delegatedListener.listener === listener) {
                    for (const event in delegatedListener.delegates) {
                        this.off((event: any), delegatedListener.delegates[event]);
                    }
                    listeners.splice(i, 1);
                    return this;
                }
            }
        }

        return this;
    }

    /**
     * Returns an array of [GeoJSON](http://geojson.org/)
     * [Feature objects](https://tools.ietf.org/html/rfc7946#section-3.2)
     * representing visible features that satisfy the query parameters.
     *
     * @param {PointLike|Array<PointLike>} [geometry] - The geometry of the query region:
     * either a single point or southwest and northeast points describing a bounding box.
     * Omitting this parameter (i.e. calling {@link Map#queryRenderedFeatures} with zero arguments,
     * or with only a `options` argument) is equivalent to passing a bounding box encompassing the entire
     * map viewport.
     * @param {Object} [options]
     * @param {Array<string>} [options.layers] An array of style layer IDs for the query to inspect.
     *   Only features within these layers will be returned. If this parameter is undefined, all layers will be checked.
     * @param {Array} [options.filter] A [filter](https://www.mapbox.com/mapbox-gl-js/style-spec/#other-filter)
     *   to limit query results.
     * @param {boolean} [options.validate=true] Whether to check if the [options.filter] conforms to the Mapbox GL Style Specification. Disabling validation is a performance optimization that should only be used if you have previously validated the values you will be passing to this function.
     *
     * @returns {Array<Object>} An array of [GeoJSON](http://geojson.org/)
     * [feature objects](https://tools.ietf.org/html/rfc7946#section-3.2).
     *
     * The `properties` value of each returned feature object contains the properties of its source feature. For GeoJSON sources, only
     * string and numeric property values are supported (i.e. `null`, `Array`, and `Object` values are not supported).
     *
     * Each feature includes top-level `layer`, `source`, and `sourceLayer` properties. The `layer` property is an object
     * representing the style layer to  which the feature belongs. Layout and paint properties in this object contain values
     * which are fully evaluated for the given zoom level and feature.
     *
     * Features from layers whose `visibility` property is `"none"`, or from layers whose zoom range excludes the
     * current zoom level are not included. Symbol features that have been hidden due to text or icon collision are
     * not included. Features from all other layers are included, including features that may have no visible
     * contribution to the rendered result; for example, because the layer's opacity or color alpha component is set to
     * 0.
     *
     * The topmost rendered feature appears first in the returned array, and subsequent features are sorted by
     * descending z-order. Features that are rendered multiple times (due to wrapping across the antimeridian at low
     * zoom levels) are returned only once (though subject to the following caveat).
     *
     * Because features come from tiled vector data or GeoJSON data that is converted to tiles internally, feature
     * geometries may be split or duplicated across tile boundaries and, as a result, features may appear multiple
     * times in query results. For example, suppose there is a highway running through the bounding rectangle of a query.
     * The results of the query will be those parts of the highway that lie within the map tiles covering the bounding
     * rectangle, even if the highway extends into other tiles, and the portion of the highway within each map tile
     * will be returned as a separate feature. Similarly, a point feature near a tile boundary may appear in multiple
     * tiles due to tile buffering.
     *
     * @example
     * // Find all features at a point
     * var features = map.queryRenderedFeatures(
     *   [20, 35],
     *   { layers: ['my-layer-name'] }
     * );
     *
     * @example
     * // Find all features within a static bounding box
     * var features = map.queryRenderedFeatures(
     *   [[10, 20], [30, 50]],
     *   { layers: ['my-layer-name'] }
     * );
     *
     * @example
     * // Find all features within a bounding box around a point
     * var width = 10;
     * var height = 20;
     * var features = map.queryRenderedFeatures([
     *   [point.x - width / 2, point.y - height / 2],
     *   [point.x + width / 2, point.y + height / 2]
     * ], { layers: ['my-layer-name'] });
     *
     * @example
     * // Query all rendered features from a single layer
     * var features = map.queryRenderedFeatures({ layers: ['my-layer-name'] });
     * @see [Get features under the mouse pointer](https://www.mapbox.com/mapbox-gl-js/example/queryrenderedfeatures/)
     * @see [Highlight features within a bounding box](https://www.mapbox.com/mapbox-gl-js/example/using-box-queryrenderedfeatures/)
     * @see [Center the map on a clicked symbol](https://www.mapbox.com/mapbox-gl-js/example/center-on-symbol/)
     */
    queryRenderedFeatures(geometry?: PointLike | [PointLike, PointLike], options?: Object) {
        // The first parameter can be omitted entirely, making this effectively an overloaded method
        // with two signatures:
        //
        //     queryRenderedFeatures(geometry: PointLike | [PointLike, PointLike], options?: Object)
        //     queryRenderedFeatures(options?: Object)
        //
        // There no way to express that in a way that's compatible with both flow and documentation.js.
        // Related: https://github.com/facebook/flow/issues/1556

        if (!this.style) {
            return [];
        }

        if (options === undefined && geometry !== undefined && !(geometry instanceof Point) && !Array.isArray(geometry)) {
            options = (geometry: Object);
            geometry = undefined;
        }

        options = options || {};
        geometry = geometry || [[0, 0], [this.transform.width, this.transform.height]];

        let queryGeometry;
        if (geometry instanceof Point || typeof geometry[0] === 'number') {
            queryGeometry = [Point.convert(geometry)];
        } else {
            const tl = Point.convert(geometry[0]);
            const br = Point.convert(geometry[1]);
            queryGeometry = [tl, new Point(br.x, tl.y), br, new Point(tl.x, br.y), tl];
        }

        return this.style.queryRenderedFeatures(queryGeometry, options, this.transform);
    }

    /**
     * Returns an array of [GeoJSON](http://geojson.org/)
     * [Feature objects](https://tools.ietf.org/html/rfc7946#section-3.2)
     * representing features within the specified vector tile or GeoJSON source that satisfy the query parameters.
     *
     * @param {string} sourceId The ID of the vector tile or GeoJSON source to query.
     * @param {Object} [parameters]
     * @param {string} [parameters.sourceLayer] The name of the vector tile layer to query. *For vector tile
     *   sources, this parameter is required.* For GeoJSON sources, it is ignored.
     * @param {Array} [parameters.filter] A [filter](https://www.mapbox.com/mapbox-gl-js/style-spec/#other-filter)
     *   to limit query results.
     * @param {boolean} [parameters.validate=true] Whether to check if the [parameters.filter] conforms to the Mapbox GL Style Specification. Disabling validation is a performance optimization that should only be used if you have previously validated the values you will be passing to this function.
     *
     * @returns {Array<Object>} An array of [GeoJSON](http://geojson.org/)
     * [Feature objects](https://tools.ietf.org/html/rfc7946#section-3.2).
     *
     * In contrast to {@link Map#queryRenderedFeatures}, this function
     * returns all features matching the query parameters,
     * whether or not they are rendered by the current style (i.e. visible). The domain of the query includes all currently-loaded
     * vector tiles and GeoJSON source tiles: this function does not check tiles outside the currently
     * visible viewport.
     *
     * Because features come from tiled vector data or GeoJSON data that is converted to tiles internally, feature
     * geometries may be split or duplicated across tile boundaries and, as a result, features may appear multiple
     * times in query results. For example, suppose there is a highway running through the bounding rectangle of a query.
     * The results of the query will be those parts of the highway that lie within the map tiles covering the bounding
     * rectangle, even if the highway extends into other tiles, and the portion of the highway within each map tile
     * will be returned as a separate feature. Similarly, a point feature near a tile boundary may appear in multiple
     * tiles due to tile buffering.
     * @see [Filter features within map view](https://www.mapbox.com/mapbox-gl-js/example/filter-features-within-map-view/)
     * @see [Highlight features containing similar data](https://www.mapbox.com/mapbox-gl-js/example/query-similar-features/)
     */
    querySourceFeatures(sourceId: string, parameters: ?{sourceLayer: ?string, filter: ?Array<any>, validate?: boolean}) {
        return this.style.querySourceFeatures(sourceId, parameters);
    }

    /**
     * Updates the map's Mapbox style object with a new value. If a style already is set and options.diff is true,
     * this compares the style against the map's current state and performs only the changes necessary to make
     * the map style match the desired state.
     *
     * @param style A JSON object conforming to the schema described in the
     *   [Mapbox Style Specification](https://mapbox.com/mapbox-gl-style-spec/), or a URL to such JSON.
     * @param {Object} [options]
     * @param {boolean} [options.diff=true] If false, force a 'full' update, removing the current style
     *   and building the given one instead of attempting a diff-based update.
     * @param {string} [options.localIdeographFontFamily='sans-serif'] Defines a CSS
     *   font-family for locally overriding generation of glyphs in the 'CJK Unified Ideographs', 'Hiragana', 'Katakana' and 'Hangul Syllables' ranges.
     *   In these ranges, font settings from the map's style will be ignored, except for font-weight keywords (light/regular/medium/bold).
     *   Set to `false`, to enable font settings from the map's style for these glyph ranges.
     *   Forces a full update.
     * @returns {Map} `this`
     * @see [Change a map's style](https://www.mapbox.com/mapbox-gl-js/example/setstyle/)
     */
    setStyle(style: StyleSpecification | string | null, options?: {diff?: boolean} & StyleOptions) {
        options = extend({}, { localIdeographFontFamily: defaultOptions.localIdeographFontFamily}, options);

        if ((options.diff !== false && options.localIdeographFontFamily === this._localIdeographFontFamily) && this.style && style) {
            this._diffStyle(style, options);
            return this;
        } else {
            this._localIdeographFontFamily = options.localIdeographFontFamily;
            return this._updateStyle(style, options);
        }
    }

    _updateStyle(style: StyleSpecification | string | null,  options?: {diff?: boolean} & StyleOptions) {
        if (this.style) {
            this.style.setEventedParent(null);
            this.style._remove();
        }

        if (!style) {
            delete this.style;
            return this;
        } else {
            this.style = new Style(this, options || {});
        }

        this.style.setEventedParent(this, {style: this.style});

        if (typeof style === 'string') {
            this.style.loadURL(style);
        } else {
            this.style.loadJSON(style);
        }

        return this;
    }

    _diffStyle(style: StyleSpecification | string,  options?: {diff?: boolean} & StyleOptions) {
        if (typeof style === 'string') {
            const url = this._requestManager.normalizeStyleURL(style);
            const request = this._requestManager.transformRequest(url, ResourceType.Style);
            getJSON(request, (error: ?Error, json: ?Object) => {
                if (error) {
                    this.fire(new ErrorEvent(error));
                } else if (json) {
                    this._updateDiff(json, options);
                }
            });
        } else if (typeof style === 'object') {
            this._updateDiff(style, options);
        }
    }

    _updateDiff(style: StyleSpecification,  options?: {diff?: boolean} & StyleOptions) {
        try {
            if (this.style.setState(style)) {
                this._update(true);
            }
        } catch (e) {
            warnOnce(
                `Unable to perform style diff: ${e.message || e.error || e}.  Rebuilding the style from scratch.`
            );
            this._updateStyle(style, options);
        }
    }

    /**
     * Returns the map's Mapbox style object, which can be used to recreate the map's style.
     *
     * @returns {Object} The map's style object.
     */
    getStyle() {
        if (this.style) {
            return this.style.serialize();
        }
    }

    /**
     * Returns a Boolean indicating whether the map's style is fully loaded.
     *
     * @returns {boolean} A Boolean indicating whether the style is fully loaded.
     */
    isStyleLoaded() {
        if (!this.style) return warnOnce('There is no style added to the map.');
        return this.style.loaded();
    }

    /**
     * Adds a source to the map's style.
     *
     * @param {string} id The ID of the source to add. Must not conflict with existing sources.
     * @param {Object} source The source object, conforming to the
     * Mapbox Style Specification's [source definition](https://www.mapbox.com/mapbox-gl-style-spec/#sources) or
     * {@link CanvasSourceOptions}.
     * @fires source.add
     * @returns {Map} `this`
     * @see [Draw GeoJSON points](https://www.mapbox.com/mapbox-gl-js/example/geojson-markers/)
     * @see [Styl